1. Field of the Invention
The invention relates to an integrated optical waveguide having a filter.
2. The Prior Art
Essays by S. E. Miller (IEEE J. Quantum Electronics, QE-8 p. 199 (1972)) and P. K. Tien (Applied Optics, vol. 10 p. 2395 (1975)) describe wave-guide structures having integrated modulators, laser amplifiers, and coupling systems.
The design and properties of multilayer filters are described for instance in the book Thin Film Optical Filters by H. A. Macleod, Adam Hilger, Ltd, (London, 1969). The theory described therein permits construction of dielectric and metallic thin films which change the spectrum or polarization properties of optical radiation or serve as reflectors.
The German Offenlegungschrift No. 2,252,826 shows a specific design of a filter with a number of high- and low-refractive layers, and provides indices of refraction and angles of incidence of lightwaves into the first layer of the multiple-layer system adjacent the waveguides which are useful with the present invention.